1. Technical Field
The method and apparatus of the present invention relate generally to an apparatus and method of constructing electric submersible brake motors. More specifically, it relates to a waterproof explosion-proof electric brake motor and an apparatus and method of modifying a commercial electric brake motor such that it may be operated in both a submersed environment and in an environment in which explosive gases are present. Explosive gas environments in which the brake motor may be operated typically comprise hydrogen sulfide or methane gases or the like.
In several operating situations, it is desirable to have a brake motor which can operate in both explosive and submersed environments. One such environment is in sewage treatment operations. In such operations, a bar rack screen is placed in the flow stream to catch debris. One such bar rack screen called the "Mensch Screen" is manufactured by Vulcan Industries of Missouri Valley, Iowa. A scrapper, driven by an electric brake motor, is employed which scrapes the screen clean of collected debris. In such environments, gases are frequently generated which have an explosive capacity, such as hydrogen sulfide, methane or the like. Additionally, depending on the depth of the flow stream, the scraper brake motor may become temporarily submersed. Consequently, it may be desirable to have a brake motor which may be operated in both explosive and submersed environments.
Currently, electric brake motors adapted to be operated in an submersible environment generally comprise conventional electric brake motors which have been encased in a water tight container. The enclosure case limits access to the brake motor when it is enclosed therein thereby requiring additional labor to effect any required service. The apparatus and method of the current invention relate to a waterproof, explosion-proof electric brake motor and modification of an existing explosion-proof brake motor, without enclosing the brake motor in a separate case. With the present waterproofing modification, the brake motor may be operated intermittently at water pressures up to 25 PSI.
2. Description of the Prior Art
Numerous electric brake motors are currently on the market. Such motors, in addition to the electric motor, comprise a brake which may be activated electrically. Several of these brake motors are also adapted to work in an explosive environment. One example of such a brake motor is the Baldor Brake motor, designated NEMA 56C through 215T-TC explosion-proof brake motors. As described above, many working environments call for brake motors which will safely operate in the presence of explosive gases. However, these so called "explosion-proof" brake motors are not adapted to be used in a submersible environment.
Some companies have developed modifications to commercially available explosion-proof brake motors to make them operable in a submersion environment. One example of such a modification, is the FMC Corporation. The FMC Corporations modifications entail housing the commercially available explosion-proof brake motor in a water tight container. However, such a method of rendering an existing brake motor submersible is limited by the physical dimensions of the water proof case. Obviously, only brake motors having a size which may fit within the case may be operated submersed by such a method. Additionally, it makes servicing of the brake motor more difficult since the brake motor must first be removed from the case before it may be worked on. Still further, a means must be developed which allows the drive shaft of the brake motor to be coupled to the external drive apparatus and thus the mounting to secure the brake motor must be adapted to accommodate the physical attributes of the enclosing water proofing case. Thus, there is a strong need for an explosion-proof, waterproof electric brake motor and a method and apparatus designed to be utilized with the conventional brake motors adapting them to be used in explosive and submersible environments, without requiring a separate enclosure case.
Therefore, a primary objective of the present invention is to provide a waterproof, explosion-proof electric brake motor apparatus.
Another primary object of the present invention is to provide an apparatus and method of water proofing a conventional explosive proof electric brake motor apparatus thereby allowing the brake motor to be used in a submersed environment.
Another object of the present invention is to provide an apparatus and method which may be quickly and efficiently implemented on existing, electric brake motors.
Another objective of the present invention is to provide a water proofing method and apparatus which may be utilized with a wide variety of commercially available electric brake motors.
A final objective is to provide method and apparatus whereby conventional explosion-proof electric brake motors may be waterproofed without the need for construction of elaborate, time consuming, or expensive enclosure cases.